C. 1 AD)
The earliest metal tools in the Philippines were said to have first been used somewhere around 500 BC, and this new technology coincided with considerable changes in the lifestyle of early Filipinos. The new tools brought about a more stable way of life, and created more opportunities for communities to grow, both in terms of size and cultural development.
Where communities once consisted of small bands of kinsmen living in campsites, larger villages came about- usually based near water, which made traveling and trading easier. The resulting ease of contact between communities meant that they began to share similar cultural traits, something which had not previously been possible when the communities consisted only of small kinship groups.
Jocano refers to the period between 500 BC and 1 AD as the incipient phase, which for the first time in the artifact record, sees the presence of artifacts that are similar in design from site to site throughout the archipelago. Along with the use of metal tools, this era also saw significant improvement in pottery technology.
Read more about this topic: Prehistory Of The Philippines, Early Metal Age (c. 500 BC